Yellow tetrazo dye and process of making same.



STATES PATENT OFFICE.

HUGO GELDERMANN, or 'GROSSLIQHTERFELDE-OST, NEAR BERLIN, GERMANY, ASSIGNOR To AOTIEN GESELLSCHAFT FUR ANILINY FABRIKATION, or BERLIN, GERMANY. I.

YELLOW TETRAZO DYE AND PROCESS OF MAKING SA ME.

rib. eeo,aea.

Specification of Letters Patent.

Patented Feb. 25, 1908.

Application filed November 6. 1907. Serial No. 400.987-

12, have invented certain new and useful Improvements in New Yellow Tetrazo Dyestultls and Processes; of Making Same, of which the following is a specification.

My present invention relates to the manu- .facture of t'etraz'o-dyestufls by tetrazotizing thioanilin di'sulfonic acid, which acid is described in the Bem'chte der Deutsche'n Chem/i- "phenol or a homologue thereof and alkylizingthe OH-grou s of the tetrazo-dyestuif thus schen Gescllschaft, Vol. XXXIX, page 611, combining the tetrazo-co'mpound thus obtained with two molecular'proportions of 8.

obtained. e coloring matters thus produced dye wool without a m'ordant from an acid bath clear yellow tints which are fast to milling, and more especially do not bleed into the white cotton when mixed cotton and .wool goods are dyedand subsequently subjected to millin In order to il ustrate m the following examples, til weight invention I give e parts being by (1). 42 parts of the sodium salt of thioani-l lin disulfonic acid are diazotized in the usual mannerin an a ueoussolution by means of 120 parts of hy rochloric acid of 12 Baum specific ravity, and 14 parts ofsodium nitrite. he solution of the 'tretrazo-co'mr poundthus obtained isallowed to run into an aqueou'ssolution of 20 parts of'phenol in '25 parts of soda-lye of 40 Baum specific ravity, and 44 parts of calcined sodium caronate. The combination being finished, hydrochloric acid is added to .the solution until the latter is of nearly neutral reaction;

on adding a suitable proportion of common formed, an excess 0 salt the dyestuif is precipltated and the mass is afterwards filtered.

In order to introduce alkyl-groups into the hydroxyl-groups of the dyestufi thus 0btamed 1t is not necessary to dry the paste of the product as above produced; one may for instance proceed as f0 ows: The-paste of the dyestulf as obtained above is dissolved in 300 closed vessel at 'to 70 C. for about 12 hours. The reaction thus being finished, the alcohol is'd-istilled oil and the residue dissolved in water which solution if necessary is brought to neutral reaction. By then add ing common salt the'product of the reaction is precipitated and is lsolated by filtering'and dry ng.

- he dyestufi thus obtained dyes wool from an acetic acid bath without a mordant clear and intense yellow tints which are fast to milling and more es ecially do not bleed into the white cotton w ich underlies the milling process together with the colored wool.

The new coloring matter possesses in the shape of the sodium salt, as above obtained,

the. formula Nrue- 0,11,00,11 N=N- o,H,.oo H this sodium salt when ulverized forms a reddish yellow powder w ich -easily dissolvesin hot water, but rather difficultly in cold water to a ellow solution. on tie addition of some concentrated sodalye se arates yellow flakes and on the addition 0 some concentrated hydrochloric acid This aqueous solution a shows a dull brown precipitate, whereas by addin some concentrated liquor ammomae the so ution is scarcely changed, the color becoming a'little lighter. In alcohol the dyestulf dissolves to a yellow solution and in .mass which is then heated in a closed vessel to about 60 C. during 6 hours. The alcohol having been removed by distillation, "the residue is dissolved in water, the solution filtered if necessary, and the product of the reaction preci )itated from the solution by the additlono common salt, whereupon the prodnot is isolated by filtering, pressing and drying.

The roductthus obtained dyes wool from an aci bath (acetic acid) clear and deep yellow shades which are fast to milling and do not bleed into the white cotton.

It is obvious to those skilled in the art that I do not limit my invention to the foregoing examples or to the details given therein. For the phenol used in the foregoing examples a homologue thereof, such as for instance orthoor'meta-cresol may be substituted. Thus by using thioanilin disulfonic acid and ortho-cresol and introducing the ethylgroup into the two hydroxyl-groups a dyestuff is obtained which dyes wool from acid bath (acetic acid) without a mordant clear and deep yellow tints which are also fast 7 to milling.

If instead of ortho-cresol meta-cresol is employed and the corresponding tetrazo-dyestuff is ethylized a dye-stuff is produced which. dyes wool from an acid bath deep yellow shades which are a little more reddish than those obtained with the corresponding dye stuff from ortho-cresol. I also state that the introduction of the alkyl groups into the OH-groups of the tetrazo-dyestufls may obviously be effected by any other suitable method than that given in my foregoing example.

Having now described my invention and the manner in which the same may be performed what I claim is,---

1 The hereinbeforc-deseribed new yellow tetra'zo-dyestufls which may be obtained by tetraz otizing thioanilin disulfonic acid, comliining'the tetrazo-compound thus obtained with two molecular proportions of a phenol and alkyliz ing'the Oll-groups of the tetrazodyestuff thus obtained, which new dyestuffs dye Wool Without a mordant from an acid bath, and more especially from an acetic acid bath, clear and intense yellow tints, which are fast to milling and more especially do not bleed into the white cotton when mixed cotton and woolcgoods are dyed and subsequently subjecte to milling, and which coloring matters when pulverized form in the shae of the sodium salt yellow powders which issolve in water and in alcohol to a yellow solution and in concentrated sulfuric acid to a blue-red to red solution.

2. The hereinbefore-described new yellow tetrazo-dyestufi having in the shape of the sodium salt the formula:

which dyestufi' may be obtained by tetrazotizing thioanilin disulfonic acid, combining the tetrazo-compound thus obtained with two molecular roportions of phenol and ethylizing the O groups of the tetrazo-dyestuif thus obtained by means of ethyl-bromid and soda-lye, which new dyestuif dyes wool without a mordant from an acid bath, and more especially from an acetic acid bath clear and intense yellow tints which are fast to v milling and more especially do not bleed into the white cotton when mixed cotton and wool goods are dyed and subsequently subjected to milling, and which coloring matter in the shape of the sodium salt when ul verized forms a reddish yellow powder wl iich easily dissolves in hot water, but rather difficultly in cold water to ayellow solution, which aqueous solution on the addition of some concentrated soda-lye separates yellow flakes and on the addition of some concentrated hydrochloric acid shows a dull brown precipitate, whereas this aqueous solution by adding some concentrated liquor ammoniae is scarcely changed, the liquor becoming a little lighter, and which new dyestuff dissolves in alcohol to a yellow solution and in concentrated sulfuric acid to a blue red solution, which solution on adding some ice separates a dull brown precipitate.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

HUGO GELDERMANN. Witnesses:

l'lENltY HAsrnn, WOLDEMAR I-IAUPT. 

